Magnetically resealable bag and methods of making the same

ABSTRACT

A magnetically resealable bag including a polymer substrate. The polymer substrate including a front panel, a back panel, a closed bottom and an opening. The inside of the opening including a first side strip and a second side strip. The first side strip and second side strip include a layer of a magnetizable composition, and at least one layer of a polymer material arranged to provide a covering over the layer of the magnetizable composition. A top portion of the first side strip is coupled to the inside at the front panel of the bag and a top portion of the second side strip is coupled to the inside of the back panel of the bag, and a bottom portion of the first and second side strip is free of the inside of the opening. The first side strip and second side strip are aligned and permanently magnetized.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.63/128,113, filed Dec. 20, 2020, the disclosure of which is incorporatedherein by reference.

BACKGROUND OF THE INVENTION

The present disclosure relates to a magnetically resealable bag and tomethods of making the same, for example, a storage bag having a magneticclosure.

An affordable magnetic re-closure feature has long been desired in thepackaging industry. However, this has not yet been practical because ofthe difficulty and cost of applying traditional magnets to a package.

Additionally, previous magnetically resealable storage bags have beenfound to lack enough magnetic strength to maintain a sufficient closure,and to ultimately leak ingredients from the magnetically resealableclosure.

SUMMARY OF THE INVENTION

In one aspect, the disclosure relates to a magnetically resealable bag,the magnetically resealable bag comprising a polymeric substrate, thepolymeric substrate comprising a front panel, a back panel, a closedbottom and an opening, and an inside and an outside, the inside of theopening comprising a first side strip and a second side strip, the firstside strip and the second side strip comprising at least one first layerof polymer material and a layer of a magnetizable composition, themagnetizable composition comprising a thermoplastic polymer andmagnetizable particles, the at least one layer of polymer material isarranged so as to provide a covering over the layer of the magnetizablecomposition, a top portion of the first side strip is coupled to theinside of the opening at the front panel of the bag, and a bottomportion of the first side strip is free of the inside of the opening atthe front panel of the bag, a top portion of the second side strip iscoupled to the inside of the opening at the back panel of the bag, and abottom portion of the second side strip is free of the inside of openingat the back panel of the bag, and wherein the magnetizable compositionof the first side strip and the second side strip are aligned andpermanently magnetized so as to form a reopenable and resealableclosure.

In another aspect, the present disclosure relates to a magneticallyresealable bag, the magnetically resealable bag comprising a polymericsubstrate, the polymeric substrate comprising a first side panel, asecond side panel, a closed bottom and an opening, and an inside and anoutside, the inside of the opening comprising a first side strip and asecond side strip, the first side strip and second side strip comprisingat least one first layer of polymer material and a layer of amagnetizable composition, the magnetizable composition comprising athermoplastic polymer and magnetizable particles, a top portion of thefirst side strip and a top portion of the second side strip comprisingthe at least one first layer of polymer material and a bottom portion ofthe first side strip and the second side strip comprising the at leastone layer of polymer material and the layer of the magnetizablecomposition wherein the at least one first layer of polymer materialforms a covering over the layer of the magnetizable composition, the topportion of the first side strip is coupled to the inside of the openingat the front panel of the bag, and the bottom portion of the first sidestrip is free of the inside of the first side panel, and the top portionof the second side strip is coupled to the inside of the opening at theback panel, and the bottom portion of the second side strip is free ofthe inside of the second side panel, and wherein the first side stripand second side strip are aligned and magnetized so as to form amagnetically reopenable and resealable closure.

Alternatively or additionally to any of the embodiments above the firstside strip comprises the magnetizable composition having a plurality ofpoles having a first leading edge comprising a first pole and the secondside strip comprises a plurality of poles having a second leading edgecomprising a second pole that is opposite to the first pole.

The magnetically resealable bag of claim 1 wherein the first side stripand the second side strip comprise the at least one first layer ofpolymer material and a second layer of polymer material.

Alternatively or additionally to any of the embodiments above the atleast one first layer of polymer material is different than the secondlayer of polymer material.

Alternatively or additionally to any of the embodiments above the secondlayer of polymer material is formed of a more compliant polymer materialthan the at least one first layer.

Alternatively or additionally to any of the embodiments above the atleast one first layer of polymer material comprises polyethyleneterephthalate.

Alternatively or additionally to any of the embodiments above the secondlayer comprises polyethylene.

Alternatively or additionally to any of the embodiments above the topportion of the first side strip and the second side strip are coupled tothe inside of the opening of the bag at the second layer.

Alternatively or additionally to any of the embodiments above, themagnetic composition comprises about 70% to about 95% magnetizableparticles and about 5% to about 30% by weight polymer material.

Alternatively or additionally to any of the embodiments above, themagnetic composition comprises about 5% to about 30% of at least onepolyethylene vinyl acetate.

Alternatively or additionally to any of the embodiments above, themagnetically resealable bag further comprises a removable top portionabove the opening of the magnetically resealable bag and the removabletop portion is laser scored above the opening to facilitate removal ofthe top portion of the magnetically resealable bag.

Alternatively or additionally to any of the embodiments above, theclosed bottom of the bag is arranged to form a stand-up pouch.

Alternatively or additionally to any of the embodiments above, thepolymeric substrate comprises a metalized foil laminated polymer.

Alternatively or additionally to any of the embodiments above, the atleast one first layer of polymer material has a thickness of about 1.0to about 2.0 mils.

Alternatively or additionally to any of the embodiments above, the atleast one second layer of polymer material has a thickness of about 0.25to about 1.0 mils.

Alternatively or additionally to any of the embodiments above, themagnetic layer has a thickness of about 8 to about 30 mils.

Alternatively or additionally to any of the embodiments above, the topportion of the first side strip is coupled to inside of the opening atthe front panel of the magnetically resealable bag and the top portionof the second side strip is coupled to the inside of the opening at thebag panel of the bag by a heat seal.

In another aspect, the present disclosure relates to a method of makinga magnetically resealable bag, the method comprising heating amagnetizable composition to a temperature at which the magnetizablecomposition is in flowable form, the magnetizable composition comprisingat least one thermoplastic polymer material and magnetizable particles,extruding the magnetizable composition at an elevated temperature to amoving transfer belt or roller with a releasable coating and marrying aheat sealable film downstream to the magnetizable composition, aligningthe magnetizable composition while the magnetizable composition is inflowable form, chilling the magnetizable composition, magnetizing themagnetizable composition, forming a first side strip and a second sidestrip of the magnetizable composition and heat sealing film, andcoupling the first side strip and the second side strip to an insidesurface of a magnetically resealable bag.

These and other aspects, embodiments and advantages of the presentdisclosure will become immediately apparent to those of ordinary skillin the art upon review of the Detailed Description and Claims to follow.

The above summary of some embodiments is not intended to describe eachdisclosed embodiment or every implementation of the present disclosure.The Figures, and Detailed Description, which follow, more particularlyexemplify these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an example bag in an open state;

FIG. 2 is a perspective view of an alternative embodiment of an examplebag in an open state;

FIG. 3 is a side schematic view of an example magnetic strip;

FIG. 4 is a side schematic view of an example polymer strip used as acovering for the magnet;

FIG. 5 is a side view of an example bag in an open state;

FIG. 6 is a side view of an example bag similar to that shown in FIG. 5in a closed state;

FIG. 7 is a side view of an example bag similar to that shown in FIGS. 5and 6 in an upside down and closed state; and

FIG. 8 is a block flow diagram illustrating an exemplary method ofmaking a magnetically resealable bag.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

For the following defined terms, these definitions shall be applied,unless a different definition is given in the claims or elsewhere inthis specification.

All numeric values are herein assumed to be modified by the term“about,” whether or not explicitly indicated. The term “about” generallyrefers to a range of numbers that one of skill in the art would considerequivalent to the recited value (e.g., having the same function orresult). In many instances, the terms “about” may include numbers thatare rounded to the nearest significant figure.

The recitation of numerical ranges by endpoints includes all numberswithin that range (e.g. 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and5).

As used in this specification and the appended claims, the singularforms “a”, “an”, and “the” include plural referents unless the contentclearly dictates otherwise. As used in this specification and theappended claims, the term “or” is generally employed in its senseincluding “and/or” unless the content clearly dictates otherwise.

It is noted that references in the specification to “an embodiment”,“some embodiments”, “other embodiments”, etc., indicate that theembodiment described may include one or more particular features,structures, and/or characteristics. However, such recitations do notnecessarily mean that all embodiments include the particular features,structures, and/or characteristics. Additionally, when particularfeatures, structures, and/or characteristics are described in connectionwith one embodiment, it should be understood that such features,structures, and/or characteristics may also be used connection withother embodiments whether or not explicitly described unless clearlystated to the contrary.

The following detailed description should be read with reference to thedrawings in which similar elements in different drawings are numberedthe same. The drawings, which are not necessarily to scale, depictillustrative embodiments and are not intended to limit the scope of thedisclosure.

This disclosure relates in general to magnetic re-closures for packagesincluding flexible packaging such as polymeric bags.

Turning now to the figures, FIG. 1 is a perspective view illustrating anexample magnetically resealable bag 10. In this embodiment, themagnetically resealable bag 10, formed in accordance with the presentdisclosure, is shown in an open state. The magnetically resealable bag10 includes two sides 12 a and 12 b, a top portion 14, a bottom portion16, and an opening 20. Opening 20 includes a front panel 21 a having afirst side strip 24 a and a back panel 21 b having a second side strip24 b. The first side strip 24 a and second side strip 24 b each includea layer of magnetic composition and at least one layer of a polymermaterial. The magnetizable composition includes at least onethermoplastic material or thermoset polymer material and magnetizableparticles. The polymer materials and magnetizable particles aredescribed in more detail below. Alternatively, the magnetizable materialmay include a thermoset material and magnetizable particles.

The first side strip 24 a and second side strip 24 b may be configuredsuch that each include at least one north pole and one south pole to 30poles for each of the first side strip 24 a and second side strip 24 b.In some instances, the first and second side strips 24 a, 24 b includemultipole magnets, each having from 1 to 22 poles per strip or about 4to 22 poles per strip. For example, an arrangement where first sidestrip 24 a includes a single magnet having a north pole the second sidestrip 24 b includes a single magnet having a south pole, for example,those made from neodymium may be formed this way, or an arrangementwherein the first side strip 24 a constitutes a magnet and second sidestrip 24 b constitutes a magnetic receptive material. The scope of thedisclosure is not limited by these arrangements provided that the firstside strip 24 a and second side strip 24 b are magnetically attracted toone another.

In some embodiments, the first magnetic strip 24 a may include a leadingedge provided with a north pole magnetic orientation, and the secondside strip 24 b may include a magnet having a leading edge provided witha south pole magnetic orientation. As a result, when the magneticallyresealable bag 10 is closed (not shown), the magnetic orientation offirst side strip 24 a and second side strip 24 b are in the properposition so as to magnetically retain the cooperating portions of themagnetically resealable bag 10 adjacent to one another during use. Thesearrangements are intended as illustrative only, and not as a limitationon the scope of the disclosure. Other arrangements and magneticorientations not specifically described herein are also contemplated.

The first side strip 24 a and second side strip 24 b thus provide themagnetically resealable bag 10 with a magnetically reopenable andresealable closure 20. These features will be explained in detail belowwith respect to FIGS. 3 and 4. While bag 10 is depicted as beinggenerally rectangular in shape, with two generally opposing, symmetricalside panels 12 a/12 b, other shapes and configurations are contemplatedincluding configurations that include additional/different side panels,additional/different end regions, different shapes (e.g., polygonal,rounded, oval, irregular, etc.), and the like.

In the embodiment shown in FIG. 1, the magnetically resealable bag 10 isshown having a laser score at 22 a and 22 b to facilitate easy openingof the magnetically resealable bag 10. The magnetically resealable bagcould also be provided with a tab, cut, or tear notch (shown in FIG. 2)at the laser score lines 22 a, 22 b to even further facilitate easyopening of the magnetically resealable bag 10.

The top portion 25 of the magnetically resealable bag 10 above the laserscore lines 22 a, 22 b may be removed by the consumer.

The magnetically resealable bag 10 may further include a hanger hole 18at the top portion 25 for hanging the bag on a rack in a store.

FIG. 2 is a perspective view illustrating an alternative example of amagnetically resealable bag 110. In this embodiment, the magneticallyresealable bag 110, formed in accordance with the present disclosure, isshown in an open state. The magnetically resealable bag 110 includes twosides 112 a and 112 b, a top portion 114, a bottom portion 116, and anopening 120. The side portions 112 a and 112 b may be heat sealed asshown at 113 a and 113 b respectively. Opening 120 includes a frontpanel 121 a having a first side strip 124 a and a back panel 121 bhaving a second side strip 124 b. The first side strip 124 a and secondside strip 124 b each include a layer of magnetic composition and atleast one layer of a polymer material. The magnetizable compositionincludes at least one thermoplastic material or thermoset polymermaterial and magnetizable particles. The polymer materials andmagnetizable particles are described in more detail below.Alternatively, the magnetizable material may include a thermosetmaterial and magnetizable particles.

The first side strip 124 a and second side strip 124 b may be configuredsuch that each include at least one north pole and one south pole to 30poles for each of the first side strip 124 a and second side strip 124b. In some instances, the first and second side strips 124 a, 124 binclude multipole magnets, each having from 1 to 22 poles per strip orabout 4 to 22 poles per strip. For example, an arrangement where firstside strip 124 a includes a single magnet having a north pole the secondside strip 124 b includes a single magnet having a south pole, forexample, those made from neodymium may be formed this way, or anarrangement wherein the first side strip 124 a constitutes a magnet andsecond side strip 124 b constitutes a magnetic receptive material. Thescope of the disclosure is not limited by these arrangements providedthat the first side strip 124 a and second side strip 124 b aremagnetically attracted to one another.

In some embodiments, the first magnetic strip 124 a may include aleading edge provided with a north pole magnetic orientation, and thesecond side strip 124 b may include a magnet having a leading edgeprovided with a south pole magnetic orientation. As a result, when themagnetically resealable bag 110 is closed (not shown), the magneticorientation of first side strip 124 a and second side strip 124 b are inthe proper position so as to magnetically retain the cooperatingportions of the magnetically resealable bag 110 adjacent to one anotherduring use. These arrangements are intended as illustrative only, andnot as a limitation on the scope of the disclosure. Other arrangementsand magnetic orientations not specifically described herein are alsocontemplated.

In this embodiment, each of the first magnetic side strip 124 a and thesecond magnetic side strip 124 b each include a top portion 140 a and140 b respectively, and a bottom portion 141 a and 141 b respectively.The bottom portions 141 a and 141 b each include at least one polymerlayer and one magnetic layer, while the top portions 140 a and 140 binclude at least one polymer layer only. The bottom portions 141 a and141 b are not coupled to the bag 110, but hang freely therefrom, whilethe top portions 140 a and 140 b are coupled to the bag 110. Thestructure of each magnetic side strip 124 a and 124 b will be describedin more detail with respect to FIGS. 3 and 4 below.

The magnetically resealable bag 110 may further include a laser score at122 a and 122 b to facilitate easy opening of the magneticallyresealable bag 110. The magnetically resealable bag could also beprovided with a tab, cut, or tear notch 123 at the laser score lines 122a, 122 b to even further facilitate easy opening of the magneticallyresealable bag 110.

The top portion 125 of the magnetically resealable bag 110 above thelaser score lines 122 a, 122 b may be removed by the consumer.

The magnetically resealable bag 110 may further include a hanger hole118 at the top portion 125 for hanging the bag on a rack in a store.

In this embodiment bag 110 is shown having a stand-up pouch 142, whichis also referred to in the industry as a bottom gusset pouch or Doyengusset pouch.

FIG. 3 is a partial side view illustrating a coextruded polymeric layer140 including a first polymer layer 143 and a second polymer layer 145.The first polymer layer 143 is suitably formed from a more compliantpolymer material than the second polymer layer 145. This particulararrangement is intended for illustrative purposes only, and not as alimitation on the scope of the present invention.

In some embodiments the first polymer layer 143 is formed from apolyolefin material, for example polyethylene, while the second polymerlayer is formed from a copolymer of an ester and an olefin, for example,polyethylene terephthalate. This structure is intended for illustrativepurposes only, and not as a limitation on the scope of the presentinvention.

It that only one layer of a polymer material 143 may be employed to wrapabout the magnetic layer, or may include more than two layers of polymermaterials.

The polymer layer 143 or layers is wrapped about the magnetic layer 144and thus configured to form a barrier to and thus prevent the contents,such as food items, contained within the bag from coming into contactwith the magnetic layer 144.

The coextruded strip 141 may then be wrapped around a magnetic layer 144to form a side strip 124 as shown in FIG. 4. The first layer 143 isshown in contact with and coupled to the magnetic layer 144 while thesecond layer 145 is an outer layer to the magnetic layer 144 and is notin contact therewith. The side strip 124 may be used to form a firstside strip 124 a and a second side strip 124 b which will be discussedin more detail with respect to FIGS. 5-7 below.

FIG. 5 is a side view of a magnetically resealable bag 110 in an openstate. Bag 110 is shown from the perspective of the first side portion112 a, and includes a top portion 114, and a bottom portion 116. Theopening 120 includes a front panel 121 a having a first side strip 124 aand a back panel 121 b having a second side strip 124 b. The first sidestrip 124 a and second side strip 124 b each include a top portion 140 aand 140 b respectively, each of which include at least one layer ofpolymer material, and a bottom portion 141 a and 141 b, each of whichinclude a layer of magnetic composition and at least one layer of apolymer material. The magnetizable composition includes at least onethermoplastic material or thermoset polymer material and magnetizableparticles. The polymer materials and magnetizable particles aredescribed in more detail below. Alternatively, the magnetizable materialmay include a thermoset material and magnetizable particles.

The top portions 140 a and 140 b are coupled to the inside surface ofthe bag. The bottom portions 141 a and 141 b are not coupled to and hangfreely from the inside surface of the bag, and form pouches 146 a and146 b between the first side strip 124 a and second side strip 124 b andthe inside surface of the bag. The pouches 146 a, 146 b are configuredto trap material 128, which will be discussed in more detail withrespect to FIG. 7.

In the embodiment shown in FIG. 5, the top portion 140 a of the firstside strip 124 a and the top portion 140 b of the second side strip 124b each include a first layer of polymer material 143 and a second layerof polymer material 145. The bottom portion 141 a of the first sidestrip 124 a and the bottom portion 141 b of the second side strip 124 aeach include a first layer of polymer material 143 and a second layer ofpolymer material which is further wrapped about a layer of magneticmaterial 144.

The first polymer layer 143 is coupled to the inside surface of the ofthe opening 120 of the bag 110 as shown at the top portion 125 a and 125b of the front panel 121 a bag 110 and back panel 121 b of the bag.Suitably, the first polymer layer 143 is more compliant that the secondpolymer layer 145 so as to allow heat sealing of the first polymer layer143 to the inside surface of the top portions 125 a and 125 b of the bag110. The top portions 125 a and 125 b of the bag are configured to allowremoval by a consumer. This can be facilitated by the addition of laserscoring and/or cuts or tabs at the sides of each of the top portions 125a and 125 b. Suitable materials for the first polymer layer 143 and thesecond polymer layer 145 used to form the first side strip 24 a, 124 aand second side strip 24 b, 124 b, according to any of the embodimentsabove, will be discussed in more detail below.

FIG. 6 illustrates a bag similar to that shown in FIG. 5 in a closedstate. The first polymer layer 143 of the top portions 140 a and 140 bof the first side strip 124 a and the second side strip 124 b arecoupled to the inside surface of the bag 110, and the second polymerlayer 145 is coupled to itself, for example, by heat sealing.

The bottom portions 141 a and 141 b of the first side strip 124 a andthe second side strip 124 b are magnetically sealed via the magneticlayer 144 of each side strip 124 a and 124 b.

The top portions 125 a and 125 b can be removed by the consumer asdiscussed above, leaving a magnetically sealed, and reopenable andreclosable bag.

FIG. 7 illustrates a bag 110 similar to that shown in FIGS. 5 and 6 inan upside down and closed state. As can be seen in this figure, thepouches 146 a and 146 b formed between the bottom portions 141 a and 141b of the first side strip 124 a and the second side strip 124 b areconfigured so as to trap material therein. This has been found to bothprevent leakage at the magnetic seal when the bag is closed, as well asto strengthen the magnetic seal.

The bag itself according to the disclosure (and/or other bag, container,etc. disclosed herein) may be formed from any suitable polymer materialincluding, for example, durable, recyclable and biodegradable polymermaterials. Examples of durable or recyclable polymer materials include,but are not limited to, polyolefins and copolymers or terpolymersthereof, for example, polypropylene and polyethylene including HDPE,MDPE, LDPE and LLDPE, polyesters and copolymers thereof, for example,polyethylene terephthalate (PET), and so forth, and mixtures thereof. Anexample of a suitable bioplastic or biodegradable material is polylacticacid. Selection of the bag material is not limiting to the scope of thepresent disclosure.

In some embodiments, the bag may be formed from HDPE or a polyester.

Layers of polymer materials and/or other materials may also be employed.For example, a polyolefin material may be employed as an inner layer,and a polyester material may be employed as an outer layer. This isintended for illustrative purposes only, and not as a limitation on thescope of the present application.

Also, for example, the magnetically resealable bags may be laminated.For example, some bags are formed from a metallized or foil laminatedpolymer material, for example, an aluminum laminated polymer material.

The magnetically resealable bags may be formed by blown film extrusionof a roll of sheet material as is known in the art. This will beexplained in more detail below as well as application of the first sidestrip and second side strip to the inside of the opening of themagnetically resealable bags. Alternatively, the resealable bags may beformed from paper or paper products or, laminated versions thereof.

The first polymer layer 143 and second polymer layer 145 may be madefrom any suitable polymer material including, but not limited to,polyolefins including polyethylene and polybutylene, polyesters,polyethers, polyamides, as well as copolymers and terpolymers, andmixtures thereof. As discussed above, suitably, the first polymer layer143 is formed of a compliant polymer material to facilitate heat sealingof the first polymer layer 143 to the inner surface of the bag. Thesecond polymer layer 145, if included, may be formed from a lesscompliant polymer material than the first polymer layer 143. Complianceof a polymer material is a term that is well understood in the art.

In some embodiments both a first polymer layer 143 and a second polymerlayer 145 are included in the first side strip 24 a, 124 a and thesecond side strip 24 b, 124 b and the first polymer layer 143 ispolyethylene and the second polymer layer 145 is polyethyleneterephthalate.

In some embodiments, the thickness of the first polymer layer 143 rangesfrom about 1.0 mils to about 2.0 mils, and suitably is about 1.5 mils.

In some embodiments, the thickness of the second polymer layer 145ranges from about 0.25 mils to about 2.0 mils, and suitably is about 0.5mils.

A heat activated adhesive, pressure sensitive adhesive or other, may besupplied between the first polymer layer 143 and the second polymerlayer 145. Optionally a heat activated adhesive, a pressure sensitiveadhesive or other, may be applied to the first polymer layer 143 tofurther strengthen the bond between the first polymer layer 143 and thebag 10, 110.

In some embodiments, a heat activated adhesive is employed that is nottacky or soft to the touch. Heat activated adhesives may bethermoplastic or thermoset. Such polymer materials used in theseadhesives include polyolefins and copolymers and terpolymers thereof,and block copolymer based adhesives.

One of ordinary skill in the art is well versed in the selection of suchadhesive material. This is not limiting to the scope of the presentdisclosure.

Optionally, the first polymer layer 143 may be substituted with a papersubstrate, with a heat activated adhesive on both sides of the papersubstrate to allow heat sealing of the paper substrate to the magneticlayer 144. In this instance, biodegradable polymer may be employed toform the magnetic layer. Certified biodegradable polymer materials aredescribed in more detail below.

The magnetizable composition forming the magnetic layer 144 of the firstside strip 24 a, 124 a and second side strips 24 b, 124 b suitablyincludes about 70 wt-% or more of the magnetizable particles as to havea sufficient attractive force for practical uses. However, it is usuallyimpractical to employ more than 95 wt-% of the magnetizable particlesbecause of production concerns, and also because of the difficulty ofretaining more than this in the binder material. Furthermore, includingmore than about 95 wt-% of the magnetic material may lead to a roughersurface.

Suitably, the magnetizable composition comprises about 70 wt-% to about95 wt-% of the magnetizable particles and about 5 wt-% to about 30 wt-%of at least one polymer material. In some embodiments, the magnetizablecomposition comprises about 80 wt-% to about 90 wt-% of the magnetizableparticles and about 10 wt-% to about 20 wt-% of at least one polymermaterial. In some embodiments, the magnetizable composition comprisesabout 84 wt-% to about 90 wt-% polymer material and about 16 wt-% toabout 10 wt-% magnetizable particles.

The thermoplastic material, often referred to in the industry as athermoplastic binder, suitable for use in the process of the presentdisclosure may include any polymeric material that is readilyprocessable with the magnetic material on, for instance, thethermoplastic or hot melt processing equipment as described in detailbelow. Such thermoplastic materials include both thermoplasticelastomers and non-elastomers or any mixture thereof.

The thermoplastic composition may be selected based on, for one, thetype of printable substrate which is being used, and the adhesionobtained between the thermoplastic composition and the printablesubstrate.

Examples of thermoplastic elastomers suitable for use herein include,but are not limited to, natural and synthetic rubbers and rubbery blockcopolymers, such as butyl rubber, neoprene, ethylene-propylenecopolymers (EPM), ethylene-propylene-diene polymers (EPDM),polyisobutylene, polybutadiene, polyisoprene, styrene-butadiene (SBR),styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene(SEBS), styrene-isoprene-styrene (SIS), styrene-isoprene (SI),styrene-ethylene/propylene (SEP), polyester elastomers, polyurethaneelastomers, to mention only a few, and so forth and mixtures thereof.Where appropriate, included within the scope of this disclosure are anycopolymers of the above described materials.

Examples of suitable commercially available thermoplastic elastomerssuch as SBS, SEBS, or SIS copolymers include KRATON® G (SEBS or SEP) andKRATON® D (SIS or SBS) block copolymers available from Kraton Polymers;VECTOR® (SIS or SBS) block copolymers available from Dexco Chemical Co.;and FINAPRENE® (SIS or SBS) block copolymers available from Atofina.

Some examples of non-elastomeric polymers include, but are not limitedto, polyolefins including polyethylene, polypropylene, polybutylene andcopolymers and terpolymers thereof such as ethylene vinyl acetatecopolymers (EVA), ethylene n-butyl acrylates (EnBA), ethylene methyl(meth) acrylates including ethylene methyl acrylates (EMA), ethyleneethyl (meth) acrylates including ethylene ethyl acrylates (EEA),interpolymers of ethylene with at least one C₃ to C₂₀ alphaolefin,polyamides, polyesters, polyurethanes, to mention only a few, and soforth, and mixtures thereof. Where appropriate, copolymers of the abovedescribed materials also find utility herein.

Examples of polymers useful herein may be found in U.S. Pat. No.6,262,174 incorporated by reference herein in its entirety. Polymericcompositions exhibiting high hot tack have been found to be particularlysuitable for use herein. Hot tack is a term of art known to those ofordinary skill.

Examples of commercially available non-elastomeric polymers include EnBAcopolymers available from such companies as Atofina under the tradenameof Lotryl® available from Arkema in the King of Prussia, Pa., fromExxonMobil Chemical in Houston, Tex. under the tradename of Escorene™,from DuPont de Nemours & Co. in Wilmington, Del. under the tradename ofElvaloy®; EMA copolymers available from ExxonMobil Chemical under thetradename of Optema™; EVA copolymers are available from DuPont′ underthe tradename of Elvax® and from Lyondell Blassell in Houston, Tex.under the tradename of Ultrathene® to name only a few.

Polyolefins or polyalphaolefins can be employed herein, or copolymers orterpolymers thereof. Examples of useful polyolefins include, but are notlimited to, amorphous (i.e. atactic) polyalphaolefins (APAO) includingamorphous propylene homopolymers, propylene/ethylene copolymers,propylene/butylene copolymers and propylene/ethylene/butyleneterpolymers; isotactic polyalphaolefins; and linear or substantiallylinear interpolymers of ethylene and at least one alpha-olefinincluding, for instance, ethylene and 1-octene, ethylene and 1-butene,ethylene and 1-hexene, ethylene and 1-pentene, ethylene and 1-heptene,and ethylene and 4-methyl-1-pentene and so forth. In some embodiments, asmall amount of another polymer may be used in combination with thepolyalphaolefin such as maleic anhydride grafted polymers which havebeen used to improve wetting and adhesion. Other chemical grafting canbe used, but maleic anhydride is by far the most common. Usually only afew percent in grafting (1-5%) are used and most tend to be ethylene orpropylene copolymers.

Examples of suitable certified biodegradable polymer materials include,but are not limited to polylactic acids or polylactides,polyhydroxyvalerate/hydroxybutyrate, and mixtures thereof.

Thermoset polymer materials may also be employed which are cured in avariety of manners such as moisture cure, radiation cure, two-partchemical reactions, heat, and so forth to form substantially insolubleor infusible materials. Such materials are well known in the art.

Thermoset polymers crosslink and/or polymerize by energy or by chemicalmeans and by a wide variety of mechanisms including, but not limited to,moisture cure, thermal and radiation cure, condensation, free radicalsystems, oxidative cures, etc. as well as combinations thereof.

Some examples of suitable thermoset materials include, but are notlimited to, polyurethanes, polyureas, polyurethane/polyurea hybrids,epoxies, acrylics, polyesters, (meth)acrylates, cyanoacrylates,silicones (polysiloxanes), polyolefins and copolymers thereof such asethylene vinyl acetate copolymers, rubbers including rubbery blockcopolymers, etc.

Each of class of thermoset material may come in a variety of differentsystems, including, for example, one and two part systems, and radiationcuring systems such as radiation (e.g. UV) curing systems, moisturecure, etc.

In some embodiments, the magnetic composition includes a multicomponentepoxy or urethane thermoset composition. The thermoset polymercompositions may also be employed in combination with magnetic receptiveparticle materials.

In some embodiments, the thermoset polymer composition is cured usingelectron beam (e-beam) radiation. Crosslinking of polymer based productsvia e-beam radiation improves mechanical, thermal and chemicalproperties. Specifically, thermal resistance to temperature degradationand aging and low temperature impact resistance are improved.

Tensile strength, modulus, abrasion resistance, resistance to creep,stress crack resistance, resistance to high pressure, and so forth areincreased.

Polymers which are commonly crosslinked using the electron beamirradiation process include polyvinyl chloride (PVC), thermoplasticpolyurethanes and elastomers (TPUs), polybutylene terephthalate (PBT),polyamides/nylon (PA66, PA6, PA11, PA12), polyvinylidene fluoride(PVDF), (meth)acrylates, polymethylpentene (PMP), polyethylenes (LLDPE,LDPE, MDPE, HDPE, UHMWPE), and ethylene copolymers such asethylene-vinyl acetate (EVA) and ethylene tetrafluoroethylene (ETFE).Some of the polymers utilize additives to make the polymer more readilyirradiation crosslinkable.

The above thermoset materials may include monomers, dimers, oligomersand polymers, as well as combinations thereof as is known to those ofordinary skill in the art.

Other suitable additives can be employed in the magnetizable compositionas well such as antioxidants and processing aids. One of ordinary skillin the art is knowledgeable as to hot melt additives.

The magnetizable composition may include any suitable magnetizableparticles including, but not limited to, various types of ferrites,strontium, neodymium, samarium and cobalt.

In some embodiments, neodymium, strontium ferrite or samarium cobalt orsome combination thereof is employed.

Magnetic materials which are particularly suitable for use hereininclude the ferrites having the general formula (M²⁺O₆Fe₂O₃) MFe₁₂O₁₉where M represents Ba or Sr.

Other examples of magnetic materials suitable for use herein include arare earth-cobalt magnet of RCO₅ where R is one or more of the rareearth elements such as Sm or Pr, yttrium (Y), lanthanum (La), cerium(Ce), and so forth.

Other specific examples of magnetic materials include, for instance,manganese-bismuth, manganese-aluminum, and so forth.

The viscosity of the magnetizable composition may range from about 5000cPs to about 500,000 cPs.

The above lists are intended for illustrative purposes only, and not asa limitation on the present disclosure. It is within purview of those ofordinary skill in the art to select other polymers without departingfrom the scope of this disclosure.

The polymer material and the magnetizable particles can be added to andmelted in mixer or an extruder, or can be supplied in the form ofpre-made pellets.

The magnetic strength of the finished product is a function of theamount of magnetic material or powder in the mix, the surface area,thickness, and method of magnetization (e.g. whether it is aligned ornot).

Coating thicknesses of the magnetic layer may range from about 8 mils toabout 30 mils.

The method of the present disclosure is not limited to any particularmagnetic material, and the scope of the disclosure is therefore notintended to be limited as such. While the above described materials findparticular utility in the process of the present disclosure, othermaterials which are readily permanently magnetized may also find utilityherein.

The magnetizable composition is heated to a temperature at which it ismolten or flowable using any suitable hot melt or thermoplasticequipment. The mixture is then supplied to a melt pump or small extrudervia any suitable means such as an auger.

In its simplest form, the method of forming the magnetically resealablebag includes heating a magnetizable composition to a temperature atwhich the magnetizable composition is in flowable form, the magnetizablecomposition comprising at least one thermoplastic polymer material andmagnetizable particles, extruding the magnetizable composition at anelevated temperature to a moving transfer belt or roller with areleasable coating and marrying a heat sealable film downstream to themagnetizable composition, aligning the magnetizable composition whilethe magnetizable composition is in flowable form, chilling themagnetizable composition, magnetizing the magnetizable composition toform a first magnet and a second magnet, forming a first side strip anda second side strip of the magnetizable composition and heat sealingfilm, and coupling the first side strip and the second side strip to aninside surface of a magnetically resealable bag.

FIG. 8 is a block flow diagram of an exemplary method of forming a bagaccording to the present disclosure. As shown in FIG. 8, themagnetizable composition is mixed and formed into pellets in a separateprocess. The pellets are then melted and extruded at a temperature ofabout 375° F. until molten. The molten magnetizable composition is thenpassed through a slot die and formed into a hot strip onto the side of atransfer belt or carrier material, such as a Teflon or Teflon coatedtransfer belt to form the magnetic layer 144.

The first layer 143 of the polymer strip 140 is applied downstream toboth sides of the magnetic layer 144 to encapsulate the magnetic layer144 therein. This assembly will form both the first side strip 24 a, 124a and the second side strip 24 b, 124 b.

A second polymer layer 145 may be already coupled to or simultaneouslymarried to the first polymer layer 143.

The magnetic layer 144 may be applied to the first polymer layer 143 ata temperature of about □□□°□F to 400° F.

The width of each layer that forms the first strip 24 a, 124 a and thesecond side strip 24 b, 124 b may range from ⅛ inch to 2 inches.

This assembly is then conveyed to and passed through a chillroller/magnetizer to permanently magnetize the magnetic layer 144.

A rare earth magnet can be used to magnetize the material used to formthe magnetic layer 144. The magnetizer can be between two poles per inchand twenty-six poles per inch. The magnetizer may be built around a drumand internally cooled. The coated material may be maintained at peakmagnetizing temperatures using a heat tunnel or other suitable means ofsupplying heat. The magnetizer may, for example, be formed fromneodymium or samarium cobalt. In some embodiments, the operatingtemperature of the magnetizer should not exceed 225° F.

In some embodiments a chill roll that is wrapped in magnets such asneodymium magnets is employed. Strontium ferrite and samarium cobalt mayalso be employed alone or in combination with neodymium magnets. Otherexamples of suitable magnets include, but are not limited to, neodymiumferrite, barium ferrite, and lead ferrite. The molten magnetizablecomposition may be aligned, chilled and magnetized in a single step asit winds around the chill roll.

The assembly is then transfer wound onto spools. Two spools, one whichforms the first side strip 24 a, 124 a and one which forms the secondside strip 24 b, 124 b are then mounted onto unwind stands on the bagforming line.

The first side strip 24 a, 124 a and second side strip 24 b, 124 b arepulled into the bag making machine and heat sealed onto the innersurface of each side of a preformed bag.

The first side strip 24 a, 124 a and the second side strip 24 b, 124 bmay be heat sealed to the inner surface of a magnetically resealable bag10, 110 at a temperature ranging from about 200° F. to about 450° F.depending on how fast the bag line is running. Line speeds may rangefrom about 50 feet/minute to about 1000 feet/minute, suitably greaterthan about 80 feet/minute to about 500 feet/minute.

The sides and/or bottom of the bag may then be passed to heat sealingstations to heat seal the sides and/or bottom of the bag to form forexample, a stand up bag or pouch.

This method is intended for illustrative purposes only. Other methods ofbag forming may be employed herein. For example, in some methods, thefirst side strip 24 a, 124 a and second side strip 24 b, 124 b includingthe magnetic layer 144 and the first polymer layer 143 may optionally beextruded and applied directly to the surface of a bag substrate or apreformed bag, rather than transfer coating as described in theembodiment above.

The finished product is then boxed and shipped to various foodsuppliers.

Those spools are then conveyed to a bag forming line, and the sides andbottom of the bag are heat sealed to make stand up bags or pouches.

The magnetically resealable bags formed according to the presentdisclosure may be employed for storage of any of a variety of items aswell as for prepackaged food products such as chips, crackers, nuts,candies, cereal, frozen foods such as frozen fruits and vegetables andso forth. This list is intended for illustrative purposes only, and notas a limitation on the scope of the present disclosure.

The description provided herein is not to be limited in scope by thespecific embodiments described which are intended as singleillustrations of individual aspects of certain embodiments. The methods,compositions and devices described herein can comprise any featuredescribed herein either alone or in combination with any otherfeature(s) described herein. Indeed, various modifications, in additionto those shown and described herein, will become apparent to thoseskilled in the art from the foregoing description and accompanyingdrawings using no more than routine experimentation. Such modificationsand equivalents are intended to fall within the scope of the appendedclaims.

U.S. Pat. No. 7,501,921 is incorporated herein by reference herein inits entirety. U.S. Pat. No. 7,128,798 to Boudouris et al., U.S. Pat. No.7,338,573 to Boudouris et al., U.S. Pat. No. 7,501,921 to Boudouris etal., US Patent Application No. 2006/0165880 to Boudouris et al., and USPatent Application No. 2017/0275056 A1 are all incorporated herein byreference.

All published documents, including all US patent documents and US patentpublications, mentioned anywhere in this application are herebyexpressly incorporated herein by reference in their entirety. Anycopending patent applications, mentioned anywhere in this applicationare also hereby expressly incorporated herein by reference in theirentirety. Citation or discussion of a reference herein shall not beconstrued as an admission that such is prior art.

While the disclosure is amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be described in detail. It should beunderstood, however, that the intention is not to limit the disclosureto the particular embodiments described. On the contrary, the intentionis to cover all modifications, equivalents, and alternatives fallingwithin the spirit and scope of the disclosure.

What is claimed is:
 1. A magnetically resealable bag, the magnetically resealable bag comprising: a polymeric substrate, the polymeric substrate comprising a front panel, a back panel, a closed bottom and an opening, and an inside and an outside; the inside of the opening comprising a first side strip and a second side strip; the first side strip and the second side strip comprising at least one first layer of polymer material and a layer of a magnetizable composition, the magnetizable composition comprising a thermoplastic polymer and magnetizable particles, the at least one first layer of polymer material is arranged so as to provide a covering over the layer of the magnetizable composition; a top portion of the first side strip is coupled to the inside of the opening at the front panel of the bag, and a bottom portion of the first side strip is free of the inside of the opening at the front panel of the bag; a top portion of the second side strip is coupled to the inside of the opening at the back panel of the bag, and a bottom portion of the second side strip is free of the inside of opening at the back panel of the bag; and wherein the magnetizable composition of the first side strip and the second side strip are aligned and permanently magnetized so as to form a reopenable and resealable closure.
 2. The magnetically resealable bag of claim 1, wherein the first side strip comprises the magnetizable composition having a plurality of poles having a first leading edge comprising a first pole and the second side strip comprises a plurality of poles having a second leading edge comprising a second pole that is opposite to the first pole.
 3. The magnetically resealable bag of claim 1 wherein the first side strip and the second side strip comprise the at least one first layer of polymer material and a second layer of polymer material.
 4. The magnetically resealable bag of claim 3, wherein the at least one first layer of polymer material is different than the second layer of polymer material.
 5. The magnetically resealable bag of claim 4, wherein the first layer of polymer material is formed of a more compliant polymer material than the at least one first layer.
 6. The magnetically resealable bag of claim 1, wherein the at least one first layer of polymer material comprises polyethylene.
 7. The magnetically resealable bag of claim 3, wherein the second layer comprises polyethylene terephthalate.
 8. The magnetically resealable bag of claim 3, wherein the top portion of the first side strip and the second side strip are coupled to the inside of the opening of the bag at the second layer.
 9. The magnetically resealable bag of claim 8, wherein the top portion of the first side strip and the top portion of the second side strip are coupled to the inside of the opening of the bag with the at least one first layer of polymer material.
 10. The magnetically resealable bag of claim 1, wherein the magnetic composition comprises about 70% to about 95% magnetizable particles and about 5% to about 30% by weight polymer material.
 11. The magnetically resealable bag of claim 1, wherein the magnetically resealable bag further comprises a removable top portion above the opening of the magnetically resealable bag and the removable top portion is laser scored above the opening to facilitate removal of the top portion of the magnetically resealable bag.
 12. The magnetically resealable bag of claim 1, wherein the closed bottom of the bag is arranged to form a stand-up pouch.
 13. The magnetically resealable bag of claim 1, wherein the polymeric substrate comprises a metallized foil laminated polymer.
 14. The magnetically resealable bag of claim 1, wherein the at least one first layer of polymer material has a thickness of about 1.0 to about 2.0 mils.
 15. The magnetically resealable bag of claim 3, wherein the at least one second layer of polymer material has a thickness of about 0.25 to about 1.0 mils.
 16. The magnetically resealable bag of claim 1, wherein the magnetic layer has a thickness of about 8 to about 30 mils.
 17. A magnetically resealable bag, the magnetically resealable bag comprising: a polymeric substrate, the polymeric substrate comprising a first side panel, a second side panel, a closed bottom and an opening, and an inside and an outside; the inside of the opening comprising a first side strip and a second side strip; the first side strip and second side strip comprising at least one first layer of polymer material and a layer of a magnetizable composition, the magnetizable composition comprising a thermoplastic polymer and magnetizable particles; a top portion of the first side strip and a top portion of the second side strip comprising the at least one first layer of polymer material and a bottom portion of the first side strip and the second side strip comprising the at least one layer of polymer material and the layer of the magnetizable composition wherein the at least one first layer of polymer material forms a covering over the layer of the magnetizable composition; the top portion of the first side strip is coupled to the inside of the opening at the front panel of the bag, and the bottom portion of the first side strip is free of the inside of the first side panel; and the top portion of the second side strip is coupled to the inside of the opening at the back panel, and the bottom portion of the second side strip is free of the inside of the second side panel; and wherein the first side strip and second side strip are aligned and magnetized so as to form a magnetically reopenable and resealable closure.
 18. The magnetically resealable bag of claim 17, wherein the top portion of the first side strip is coupled to inside of the opening at the front panel of the magnetically resealable bag and the top portion of the second side strip is coupled to the inside of the opening at the bag panel of the bag by a heat seal.
 19. The magnetically resealable bag of claim 17, wherein the first side strip and the second side strip comprise the at least one first layer of polymer material and a second layer of polymer material.
 20. A method of making a resealable package, the method comprising: a) heating a magnetizable composition to a temperature at which the magnetizable composition is in flowable form, the magnetizable composition comprising at least one thermoplastic polymer material and magnetizable particles; b) extruding the magnetizable composition at an elevated temperature to a moving transfer belt or roller with a releasable coating and marrying a heat sealable film downstream to the magnetizable composition; c) aligning the magnetizable composition while the magnetizable composition is in flowable form; d) chilling the magnetizable composition; e) magnetizing the magnetizable composition to form a first magnet and a second magnet; f) forming a first side strip and a second side strip of the magnetizable composition and heat sealing film; and g) coupling the first side strip and the second side strip to an inside surface of a magnetically resealable bag. 